Degreasing apparatus



May 15, 1944. w. D. PHILLIPS Erm. 2,349,001

DEGREASING APPARATUS Original Filed Aug. 3. 1940 Jy'- @ff f TW Patented May 16, 1944 Willard D. Phillis andi Ralph A. VanFossen, hicago, Ill.

original application Amst s, 1940, serai No. 351,018. Divided and this application February 1s, 194s, serial No. 415,917

(ci. 2oz-17o) 2 Claims.

This invention is a division of our co-pending application, Serial No. 351,018, led August 3, 1940, and is an improvement on our degreaser fully described in our Patent 2,253,579 issued August 26, 1941. One of the objects of the invention is to provide a degreasing cabinet with a new and novel mechanical design wherein a cabinet of comparatively small size and weight is arranged to include a relatively large vapor treating chamber adapted to handle large and heavy machinery.

The particular object of the invention is to provide a novel vapor control combination comprising a vapor level control device to establish a normal vapor level within the vapor chamber; and a thermally active radiating surface on the exterior of the vapor chamber to increase surface radiation and thereby facilitate condensation of vapors above the normal vapor level.

Referring now more particularly to the drawing:

Fig. 1 is a side'elevational view partly in section illustrating the novel means for controlling the vapor level in a degreaser chamber;

Fig. 2 is a wiring diagram of the electrical circuit of the typical'degreaser apparatus;

Fig. 3 is a perspective view illustrating the application of the vapor control means on a modified type of cabinet; and

Fig. 4 is a fragmental sectional view taken substantially on the plane of the line l-l in Fig. l.

Now referring to the drawing, the degreasing apparatus illustrated in Figs. 1 to 4 inclusive, includes a rectangular degreasing cabinet |5| or a cylindrical degreasing cabinet |52, either of which may be arranged to include the thermostatic vapor controlled devices more fully illustrated in our Patent No. 2,253,579, issued August 26, 1941, and which may. also be provided with a new and novel means to assist in maintaining the uniform vapor level and preventing hydro-carbon vapors from escaping from the degreasing cabinet. T'he vapor chamber illustrated in Fig. 1 comprises a thin sheet metal cylindrical body portion |53 terminating at its upper extremity in a beaded reinforcing rim I5I'and terminating at its lower extremity in a beaded rim |55 interconnecting with the bottom portion |55 of the chamber. The bottom portion |56 extends inwardly and is joined to the walls of a cylindrical chamber or vaporlzing sump |51 at a point somewhat below the upper extremity of the cylindrical walls to provide an upstanding partition to deilne a distillate receiver or sump |55 between the cylinder |51 and the outer cylinder |55. The sump |51 has a bottom |55' having a shelf flange |5| in which a heating element |62 is mounted. The entire unit is supported on three legs IBS-preferably welded to the cylindrical vapor chamber |53 and provided with casters |64 or other friction-reduction devices to facilitate easy,v convenient movement of tl entire unit.

If desired, a cover may be provided and a flushing pump 55, inciudlnga sediment pump |68 and a manually operable flushing nozzle |61.

'I'hese mechanisms form no pertinent part of the present invention, however, and will, therefore, not be described in further detail.

In any type of degreasing apparatus itis of utmost importance to provide a satisfactory means for controlling the vapor level and for preventing hydro-carbon vapors from escaping from the apparatus into the surrounding air. This is particularly true, of course, in an apparatus designed as a portable unit to be used in a crowded factory location in close proximity to other workers or in closed and comparatively poorly ventilated industrial plants. In this connection it is pointed out that in order to be satisfactory for use in a crowded factory building, it is essentialthat the hydro-carbon vapors utilized as the active element in degreasing equipment be properly and effectively confined within the degreasing apparatus, since the presence of undue vapors in the air introduces an unpleasant atmosphere, and if the concentrationr of vapors rises above a minimum, it may be actually harmful for persons working in the` vicinity for long periods of time. This situation has been recognized by the public health authorities in practically every locality and a1- most every community has in effect public health regulations defining the maximum concentration of hydro-carbon vapors legally allowable in industrial locations.

It will be appreciated that although the hydrocarbon vapors used are approximately five times more dense than air, yet they are not sufficiently dense to satisfactorily operate float valves or other such devices commonly utilized to control fluid levels, but inasmuch as the body vapor within the chamber will always be at an exactly uniform temperature, and since any cooling of the vapor will reconvert it into liquid, this invention seeks to take advantage of these characteristics by providing vapor control devices including a thermostat |1| on the side wall of the vapor chamber |55 at a point substantially above the bottom of the chamber but substantially below the upper rim |54. As hereinbefore pointed out, the hydro-carbon vapors are approximately ilve times heavier than air and thus as the liquid is` heated and vapor begins to form, it will slowly rise to a uniform level throughout the chamber until the upper level or the vapor reaches the thermostat.

It is understood, oi' course, that the critical temperature of the thermostat I1I is adjusted to be below the boiling point of the solvent so that whenever the high temperature vapor contacts the thermostat,Y the thermostat may act through the electrical switch |12 to ,open the,

electrical circuit through the heating element |62 and prevent the further production of vapor. Similarly, as the vapor condenses by contact with the work or the side walls of the vapor cabinet, the vapor level will gradually fall until it is below the level oi the thermostat |1|. As this occurs the air from the atmosphere of the room will be drawn into the chamber and will contact the thermostat |1| and since this air is at a temperature far below the boiling point of the solvent, it will actuate the thermostat to again close the circuit through the heating element |62. The electric heating element |62 is also provided with a tubular temperature thermostat bulb |13 connected to the pressure switch |12 by an operating tube |14.

As thus far described, the vapor control devices are identical with those disclosed in our Patent No. 2,253,579, issued August 26, 1941, but in the present invention a substantial improvement in the eiliciency of operation has been obtained by providing exterior surfaces of differing thermal characteristics on the outside of the vapor chambers |5| or |52. In small portable units it is essential that the wall structures be made of a single thickness of comparatively light sheet metal, as for example, the metal sheet |8| illustrated in Fig. 4, and this sheet metal is customarily galvanized or otherwise coated with corrosion-resisting material forming an interior layer |8| and an exterior layer |83. In case of ordinary galvanized metal these two layers are comparatively highly polished and tend to reect the heat within the chamber rather than to radiate it into the outer air. Thus while a certain degree of condensation takes place on the walls |53, yet itis comparatively small because of the low radiating characteristics of the polished surfaces |82 and |83. The low radiating characteristics of the side Walls |53 are ordinarily desirable, since an overly rapid condensation of the vapor on the side Walls will of necessity call for acorrespondingly large capacity of the heating unit |62 in order to maintain the solvent level at all times.

In the event that the solvent level should be disturbed, however, either by the introduction of large objects into the chamber or by violent currents of air in proximity to the apparatus, it is desirable to instantly condense any hydrocarbon vapors which may tend to rise above the normal vapor level in order 'to prevent these vapors from escaping into the atmosphere. To accomplish this we provide a. thermally active coating |84 on the exterior surface of the chamber ISI or |52 and extend it downwardly from the upper rim of the chamber to a point at the approximate level maintained by the vapor con# trol thermostat |1|. The thermally-active coat- .ing |84 may be of metallic or non-metallic composition vand highly satisfactory results have been obtained by utilizing ordinary black paint, since the black surface of the portion |84 will have a considerably higher capacity for radiation than the bright galvanized surface |83. The higher radiating characteristics of the surface |84 will cause the upper portion of the side walls |53 to remain at a comparatively cool temperature at all times. Thus, in the event that the vapor level is disturbed, any swirling currents of vapor tending to rise above the rim of the cabinet will be eiectively prevented from escaplng since they will iirst strike the relatively cool side walls and be instantly condensed into liquid which will drop into thel receiving sump |53.

Having thus shown and described our invention, we claim:

1. In a degreasing apparatus, the combination of a vapor chamber, means to supply vaporized solvent within said chamber, vapor level con-4 trol ldevices to establish a normal solvent vapor level in said chamber, and a radiating surface on the exterior of said vapor chamber above the normal solvent vapor level, said radiating surface being characterized by heat radiating properties greater than the heat radiating properties of other portions of the vapor chamber.

2. In a degreasing apparatus, a vapor chamber including side walls of thin, light sheet material having high heat conducting characteristics, said chamber having parallel, vertical side walls terminating at their upper extremity in an unobstructed mouth of area not substantially less than the area of the vapor chamber, a solvent vaporizing sump, an electrical heating unit in said vaporizing sump and adapted to be submerged in liquid solvent, a vapor-actuated control for said heating unit, said vapor-actuated control beingpositioned at a point substantially below the top of said side walls and substantially above the bottom of the vapor chamber, and a thermally-active coating on the exterior surface WILLARD D. PHILLIPS. RALPH A. VAN FOSSEN. 

